Even more on Ashkenazi ancestry

There’s yet another paper out on Ashkenazi ancestry. It’s clear that this problem is a bit tricky, because the ancestral groups are not as different as one would like – this makes distinguishing the origins of chromosomal segments more difficult. Drift doesn’t help. So they check out and calibrate various algorithms with simulated scenarios, which makes sense.

Here they’re looking at finer details. When they analyze the origins of the European component of Ashkenazi ancestry, they conclude that most is southern – probably Italian, but that smaller amounts originated from (probably) Western Europe and (more certainly) Eastern Europe: and in that temporal order. They conclude that the Italian admixture slightly predated a late medieval founder event. Different methods came up with somewhat different estimates for the total amount of European ancestry: the local ancestry inference (LAI) approach came up with 53% European, while the GLOBETROTTER analysis came up with an estimate of 67% European ancestry (after calibration by simulations). In their best guess, they split the difference and go for 60% European.

To sum up, their model is that a population from the Levant mixed with Italians, and shortly thereafter moved to the Rhineland (the founding bottleneck), perhaps mixing to some degree with the local Europeans there, and certainly mixing some with Slavic types when they moved to the Polish-Lithuanian Commonwealth.

How do their conclusions differ from those in the last report? Previously they were thinking that the bottleneck was around 1350, a product of the Black Death and savage persecution – now they’re talking the original settlement in the Rhineland. Previously they had a somewhat lower estimate of European ancestry (~48%, now 60%). I thought these two conclusions likely a couple of years ago.

The big new point, important if correct, is that the admixture with Italians is relatively recent – too recent to have happened back in Roman times. In their model, this main admixture event is 25-55 generations ago, while the founding bottleneck is 25-35 generations ago. It’s not impossible that the admixture happened at the same time as the founding. This I didn’t expect.

How to improve our understanding? aDNA – dig we must!

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75 Responses to Even more on Ashkenazi ancestry

  1. SonOfRekab says:

    I thought i read here (or somewhere else) some time ago, that it was a small founding group of mostly ME males with southern European women that mixed and endogamy was set after a few generations.

    Sounds like exactly what you are describing here, no?
    What is new here?

    • gcochran9 says:

      Well, I had thought that the original admixture was probably in Rome, in late republican and early Imperial times: we know that there were Roman Jews back then.

      But maybe the timing is wrong.

      It may be that those populations faded away and then a similar admixture happened again.

      • Anonymous says:

        Italian women who migrated separately to the Rhineland ?


        • When jewish men had established themselves to be financially successful they then turned to find brides. That they imported them from where they came from rather than where they established their business isn’t that surprising. That is a plausible explanation for this.

      • syonredux says:

        “It may be that those populations faded away and then a similar admixture happened again.”

        Yeah. That’s the part that I find difficult to work out.The earlier model ( admixture in late Republican/early Imperial Rome) was a lot cleaner and simpler to understand. This is just strange.

  2. Matt says:

    …in secret, dark digs – http://phys.org/news/2016-07-israel-mystery-biblical-philistines.html

    “The archaeologists kept the discovery a secret for three years until the end of their dig because of a unique hazard of archaeology in modern-day Israel: they did not want to attract ultra-Orthodox Jewish protesters, Master said.

    “We had to bite our tongues for a long time,” Master said.

    In the past, the ultra-Orthodox have staged demonstrations at excavations where human remains are found, arguing that the remains could be Jewish and that disturbing them would violate a religious prohibition.”

  3. So the 1 sd advantage in intelligence over other Europeans has been established in 35-55 generations?

    • gcochran9 says:

      We know when the Rhineland communities started. Sufficient time, I think.

    • gcochran9 says:

      And it may have happened more than once, via a similar process. The Jews of Spain aren’t the same population as the Ashkenazim, but probably originated in a similar way, and may have experienced similar selective pressures. I don’t have much data, but they may well be smarter than the average bear. But most of the Asian/North African Jews seem not to be.

      • j says:

        When you say Levant, you are not referring to the current population of the Middle East. More like Phoenician – probably similar to Lebanese Christians today.

        Bagdadi and Aleppo Jews are very remarkable too.

        • dearieme says:

          I was going to ask “which part of the Levant”? Do we know what the researchers used as their base group for Levantines?

      • Anon says:

        Even North African and Middle Eastern Jews seem to have a significant IQ advantage to the base population. 1 SD above Arabs is still below average.

        • Jim says:

          What average? World average is about 90. Arab populations seem to range from the low eighties in South Arabia to the high eighties in places like Iraq. One standard deviation above Arab populations is well above the world average.

      • Jay says:

        Are there latitudinal differences in Ashkenazi IQ with those in the west being higher? The indigenes west of the Hajnal line may have been juicier hosts if they were more altruistic in a non-nepotistic way. Cooperative indigenes = good for duping, but having higher IQ’s themselves, this combination could have set up the strongest selection for Ashkenazi verbal skills among all the diaspora populations.

  4. TipTipTopKek says:

    In their model, this main admixture event is 25-55 generations ago, while the founding bottleneck is 25-35 generations ago.

    So where where the Jews between 630 AD and 1390 AD (midpoint 1010 AD) and what was happening that might have moved a bunch of Jews to italy? The First Crusade was 1095 AD. Wars of St. Sabas in the 1200s. In 1244 AD Jerusalem was lost to the Muslims again.

    The fall of Jerusalem in 1244 AD seems a likely event that fits the timeline, it’s 30 generations ago. Is it possible that the bottleneck happened to the Jews via the migration post this event and was followed almost immediately thereafter by the admixture with Italian women, and then a migration to the Rhineland?

    • gcochran9 says:

      Obviously not. The Rhineland community existed more than 200 years earlier.

      • st says:

        So the event must have happened in the frame 500 AD – 900 AD. Did it have to be in the western part of the roman empire? This “italian” dna, it might look italian nowadays, but can we tell what would it look like in the context of the long gone eastern roman and byzantine provinces from 6-10th century ad? The “italian dna” easily could have come from some byzantine princess from Constantinople entering dynastic marriage with prominent family from the middle east, happening to be jewish.
        Anyway the frame of admixture opens the doors of the possibility that the dna looks italian for the lack of the better proxy. The period is very near to the turbulent times of the fock -wandering period – several groups entering italy starting with the huns in 5th century, the fall of Rome in 476 AD, langobard and gothic (and few other ethnicities as well) entities in italian peninsula; then Justinian the Great from the Eastern Roman Empire takes over the power in Rome and restores the roman empire in a short-living spel from iberia, north africa, Italy, Rome included to Judea – Jerusalem included -and unites the mediterranean region for last (for now) time; But this ghost of Rome disappears within a century, however, with roman power restored in Italy during 6th century, we can’t rule out that the predecessors of ashkenazim were (forcefully?)relocated to rome by the byzantines and could have been picked as hostages from anywhere.
        The next critical period is around 600 AD – Nicephorus Foka (of roman blood, the ancient rumors say) makes an amazing counterattack with the byzantine army, while persian armies are at the doors of Constantinople and look as if the last day of Eastern Roman empire has come as well; Foka crosses Caucasus, central asia and hits persia’s back from what is now afghanistan. Instead of entering Constantinople, Persia surrenders and is left to the mercy of Byzantines/eastern romans; Foca comes back to ERI with hostages from persia – lots of them. Could that have been the founding event of ashkenazi community?
        In 630 AD Islam emerges as the great power of middle east – with a lot of turmoil to follow for the middle eastern provinces of Byzantium – they are lost again, this time to the arabs. Yet Bizantia kept some of its italian colonies to as late as 8th century, possibly till later. With ongoing wars in its middle eastern provinces (all lost) lots of opportunities for human exchange b/n the middle east and Italy.
        And there are even more options. Very interesting finding.

        • gcochran9 says:

          “The “italian dna” easily could have come from some byzantine princess from Constantinople entering dynastic marriage with prominent family from the middle east, happening to be jewish.”

          That’s a particularly nutty scenario. Jews were always on the shit list in the Byzantine Empire: mostly tanners, in Constantinople. In Palestine, distrusted.

          • st says:

            I know. don’ t beleive it for a second. i am trying to tell you that For more than a century in that time frame Italy had been Byzantine province. are you saing that bizantines would marry jews in Italy but not in Constantinople. in fact nutty or not if the ashcenazi do cary italian dna from this period, it did happen. Btw there were no pagans inItaly at this time so it gets even nuttier. they did not just married bysantine princeses they married christians.
            now about that general, Belisarius, who destroyed Vandal kingdom in Africa. Jewish community in Constantinople convinced him to dispose of the kevot. i mean they were influencial enough to be listened to by the supreme commander of the byzantine army. not autcasts.
            i can tell you a lot more but i dont see why. actually many of thr byzantine princeses were not byzantines – for example Chechek from 8th century. She was not even christian.

            • panafancypants says:

              Sounds kind of like the Khazar thing.

            • Bla says:

              Lombards were partially pagans, partially Arians when they started to take over from Byzantines. Even when they converted to Catholicism (let’s not nitpick if it is a correct term for that era and keep it for the sake of simplicity) I believe they didn’t make any laws concerning specifically Jews, and it is possible no fuss was made about Jewish men marrying local Catholic women.
              Guess neither would Carolings, since under Luis the Pious they could own and sell Christian slaves (but not to non-Christian buyers).
              Ostrogothic Kingdom also looks quite possible, but probably too early.

              • dearieme says:

                “Even when they converted to Catholicism (let’s not nitpick if it is a correct term for that era and keep it for the sake of simplicity)”: surely your term is entirely for the era. The common error is referring to Roman Catholics simply as “Catholics”.

                You can argue that the last Catholic monarch of England was Henry VIII, who kept the ideology but dropped the “Roman” bit, essentially appointing himself Pope of England.

                Bloody Mary and James II were Roman Catholics.

                There, that’s English history sorted out. Back to the Ashkenazi question.

                P.S. Why don’t the extreme political opponents of modern Israel refer to the AshkeNAZI? Are they too dim to have thought of it?

      • TipTipTopKek says:

        Did that community predate the Crusades? What’s the earliest date known for it, IMO that’s a starting point to brainstorm events which would have cause the migration.

        • gcochran9 says:

          Yes it did. Go read lots of books.

        • Josh says:

          Money lending? Italian city states get back in the international trade game, start collecting taxes and paying wages in specie and bring in Jews to lend specie to the lower classes.

          • st says:

            “The common error is referring to Roman Catholics simply as “Catholics”.”
            No. Actually, the common error is not knowing that there were no “catholic” and “orthodox” churches prior to 11 century AD, when the schism between the western and eastern clerics occurred and roman catholicism and eastern orthodox church came into being as a result.
            That is what Bla was referring to – applying the term “catholic” to any christian denomination that existed prior to 11 century AD is not correct.

            • dearieme says:

              On the contrary, “Catholic” and “Arian” Christians hog the history books for centuries before the Pope’s great flounce-out of 1054.

              • Anonymous says:

                Do you know what the word “Catholic” stands for?
                It is from Byzantine-Greek word “catholicos”, which is just the Greek word for “everyone’s”, meaning “universal”. It is an epithet containing the claim for ultimate universality. The western clerics went with this claiming legitimacy, but it was just a legacy from the good’ol times before the schism. Orthodox did not abandoned the claim neither – the Constantinople patriarchs were “catholicos”, that was their title – and still is, BTW. It simply means “universal”, “of all”. Armenian church, which was the first to split (really early, 5th century) from mainstream Christianity is also led by a “catholicos” – again this epithet is a claim for legitimacy and not a definition for denomination – not before 11th century. Until 11 century each verdict or decree from Constantinople’s church hold legal power in Rome as well and vice versa – whatever decree the pope would issue in Rome would have been valid in Constantinople as well.
                So – no catholic denomination before the schism in the 11th century and no orthodox church on the east before this time. No Catholic church. Got it?
                But you would not find it strange that the western clerics picked a Greek word for their denomination and not a Latin one, would you.
                Now about the arianics heresy. Levant was full of heresies at this time; the closer to the original source,, the bigger the theological diversification in the theological scholarship – a little bit like in biology; the monks who baptized some of the Germanic tribes happened to be part of the arianics movement. Germans did not know this. Arians (after a name of a monk named Arian) believed that Christ was only a human messenger. They denied his divine nature. After being a (minority) part of the theological scholarship for almost a century, the arianic theologians got cast out and the movement was pronounced heretical – both east and west. Some German kingdoms and tribes that got baptized by the wrong theologians switched back to mainstream, some did not -not immediately; it took them awhile until they found out they’ve been subscribed to the illegitimate version of Christianity. Nothing to do with the schism that happened 5 centuries later.
                Go read the rest in internet. Europe was a mosaic of christian dioceses – some paying their taxes to Rome and some to Constantinople. So eastern and western clerics fought over each newly acquired diocese – where should the tax money go, Rome or Constantinople? The missionaries were competing who will baptize who. But there were no theological differences and there was a single denomination until the schism. Of course, putting Armenia and Eritrea aside. Speaking of Armenian paulicians, some of them sided with the Islam and formed unified force in 7th century, this unified force lasted for more than 2 centuries and at times was controlling entire Anatolia – and of course, Judea. In the mean time at least two byzantine emperors from the epoch were paulicians by birth – Leo Isavrius and Nichephorus Genik. Constantinople. I mean Christianity was far from being an absolute power in Byzantium. They had to maneuver – sometimes appointing people not belonging to their faith as emperors; and yes, (possibly) Jewish or pagan princesses like Checheck would even become Byzantine empresses. The Islamic conquest of Persia made the things even more complicated – thousands of pagan Zoroastrians (magi) asked for refuge in Byzantium – and were granted refugia without being required to change their faith – a little bit like the Syrian refugees being granted Refugio in christian Germany nowadays. Were the predecessors of Ashkenazim part of the ancient Babylonian Jewry or part of medieval Persian Jewry, seeking better place under the sun after the turmoils caused by the Islam and Patriian troops in the Levant or Byzantine forces in Persia? Not to me to say.

                And yes, the ancient DNA sequenced in the Balkan roman provinces from the period 4-7 century AD is definitely “Italian” -it goes strait among the contemporary northern Italians on the DNA plots, only it it 1500 years old and not from Italy.

              • dearieme says:

                “Do you know what the word “Catholic” stands for?” Indeed I do. Or, more accurately, what “catholic” means.

                “So – no catholic denomination before the schism in the 11th century and no orthodox church on the east before this time. No Catholic church. Got it?” Golly, you are as ignorant as you are offensive. Take your eyes off Wikipedia and go and read some history books. You will see that discussions of the Dark Ages routinely refer to the distinction between Catholic and Arian Christianity. Those historians are too well informed to confuse “Catholic” with the more recent “Roman Catholic”. They even know, most of them, that “Arian” was rather a misattribution originally, but no matter, the usage had become customary.

                You apparently want to give the Pope’s followers monopoly use of “Catholic”. Tough: centuries of usage say you are wrong.

  5. Andrew says:

    Historically, there is the Embriaci family that lived in Castile, Genoa, and Pisa in the 11th century. They claimed to descend from the Jewish Exilarchs (royalty) and were influential in Italy for some time.

  6. dearieme says:

    By what mechanism were there lots of nubile Italian women available? Prisoners of war/slaves? Their husbands and potential husbands dying in war?

    • gcochran9 says:

      I think we’re talking about a couple of hundred or so.

    • AppSocRes says:

      As a people and individually Jews were respected by upper class Romans for their probity and adherence to moral behaviors that Romans nostalgically associated with their Republican past. Many upper class Romans attended synagogues and adopted parts of the Jewish moral code without converting. I’d surmise that it would have been relatively easy for a Jewish male to have found a Roman or Italian wife. Conversion would have been relatively eassy for such a woman.

      • gcochran9 says:

        An inaccurate oversimplification. Most Classical writers had a negative view of the Jews (see Tacitus) – a few did not. By the first century some Gentiles had developed favorable views, were interested and sympathetic: more in the Eastern half of the Roman empire. A lot of we have on the subject comes from Josephus (as in the Jewish War) and I wouldn’t trust him.

        As for pagan converts to Judaism, we simply have very little information. Known number of cases in Rome is something like six.

        Things became more difficult after the Jewish revolts the First Jewish–Roman War (66–73 AD), the Kitos War (115–117 AD), and the Bar Kokhba revolt (132–135 AD).

        As a practical matter, I sincerely doubt if hordes of POWs snagged many aristocratic chicks.

        Anyhow, if these calculation of the admixture time between Italians and Levanters is correct, all this late Republic/early Empire stuff is irrelevant.

  7. Cplusk says:

    Question: Were financiers like Aaron of Lincoln, Aaron of York, Josce of Gloucester and Vivelin of Strasbourg Ashkenazi?

      • Cplusk says:

        Then either they got the intelligent adv very quickly or nobody else in Europe was interested (or allowed?) in finance. Ashkenazi population during those times must be extremely small yet they have the richest guys in England and HRE.

        • syonredux says:

          “Then either they got the intelligent adv very quickly or nobody else in Europe was interested (or allowed?) in finance.”

          The Catholic Church frowned on charging interest:

          “The First Council of Nicaea, in 325, forbade clergy from engaging in usury[5] which was defined as lending on interest above 1 percent per month (12.7% APR). Ninth century ecumenical councils applied this regulation to the laity.[5][6] Catholic Church opposition to interest hardened in the era of scholastics, when even defending it was considered a heresy. St. Thomas Aquinas, the leading theologian of the Catholic Church, argued that the charging of interest is wrong because it amounts to “double charging”, charging for both the thing and the use of the thing.
          In the medieval economy, loans were entirely a consequence of necessity (bad harvests, fire in a workplace) and, under those conditions, it was considered morally reproachable to charge interest. It was also considered morally dubious, since no goods were produced through the lending of money, and thus it should not be compensated, unlike other activities with direct physical output such as blacksmithing or farming.”


        • Henk says:

          Fascinating, thanks! This new timeline seems to allow for the possibility that the AJ’s European fraction was European Christian moneylender families “fleeing” into Judaism (and intermarrying) when the Church started to crack down on them (ninth century, according to syonredux’s wiki quote.)

          If true, then yes, they would have started out intelligent, rich, and already deeply entrenched in the European moneylending business.

          • dearieme says:

            I suppose you imply that those Christian moneylenders married their daughters into Judaism?

            I ask this on the assumption that it’s the male line that’s of dominant Levantine origin. If I’m wrong I’ll surely be corrected.

            • Henk says:

              Well, not “married off”. In this narrative (spun for entertainment purposes only, mind you), rich European moneylenders converted themselves, their money, and their families to Judaism for business purposes.

              Theoretically, this move took their children out of the Christian marriage market and put them onto the Jewish one.

              From the Jewish marriage market’s perspective, our hypothetical neo-Jews probably didn’t look and smell all that Jewish yet. Consequently, “real” Jews might have been reluctant to allow a daughter to marry a faux-Jew, although less “protective” of a son. In this narrative, their mixed offspring would have had more old-Jewish fathers and more neo-Jewish mothers.

              An opposite bias might have driven back-conversions to Christianity for sons of neo-Jews.

  8. MawBTS says:

    Why aren’t Sephardic Jews intelligent? Wouldn’t the theorized mechanism for Ashkenazi intelligence (white-collar specialization) have applied to Jews living in Spain?

    • gcochran9 says:

      Spanish Jews were not as occupationally specialized: more of them farmed. But there was also some similarity in occupational profile – moneylending, tax farming, etc.

      • MawBTS says:

        I see.

        I don’t have numbers, but weren’t a decent number of intellectually exceptional Jews from 1100-1800 Sephardic? Thinking of Maimonides, Spinoza, Ricardo, and Disraeli.

        Ashkenazic dominance seems like a recent thing – only a couple of centuries old. But that makes sense if whatever happened to the Ashkenazi was a stronger version of what happened to the Sephardi. At first, relative parity between the groups. But gradually, the gap widened.

        • Cplusk says:

          It’s not about the intelligence gap, Ashkenazi population was too small to produce geniuses until the post 1750 population explosion.

          • syonredux says:

            “It’s not about the intelligence gap, Ashkenazi population was too small to produce geniuses until the post 1750 population explosion.”

            It’s about the culture gap. Traditional Jewish culture was focused on producing businessmen and Talmudic scholars, not scientists and artists.Cf Spinoza, for example, who had to abandon the Jewish community in order to become a philosopher.

            Things only really started to change with the Haskalah movement in the late 18th century and Jewish Emancipation/integration in the 19th.

            • syonredux says:

              “In an essay on Sephardi Jewry, Daniel Elazar at the Jerusalem Center for Public Affairs[76] summarized the demographic history of Ashkenazi Jews in the last thousand years, noting that at the end of the 11th century, 97% of world Jewry was Sephardic and 3% Ashkenazi; by the end of XVI century, the: ‘Treaty on the redemption of captives’, by Gracian of the God’s Mother, Mercy Priest, who was imprisoned by Turks, cites a Tunisian Hebrew, made captive when arriving to Gaeta, who aided others with money, named: ‘Simon Escanasi’, in the mid-17th century, “Sephardim still outnumbered Ashkenazim three to two”, but by the end of the 18th century, “Ashkenazim outnumbered Sephardim three to two, the result of improved living conditions in Christian Europe versus the Ottoman Muslim world.””

              Even with higher population levels, AJs during the period 1650-1800 still weren’t producing quality work in STEM and the arts.Neither were the Sephardim (Spinoza and Ricardo both abandoned the Jewish community). Traditional Jewish culture simply didn’t care about science and the arts.

              • syonredux says:

                Circa 1755, Scotland’s population was 1,265,380 persons. 18th century Scotland produced James Watt, David Hume, Adam Smith, Joseph Black, James Hutton, etc

      • Maybe the fact that Sephardim farmed is the “result” of their lesser intelligence rather than the cause of it. One cannot “force” someone to a white collar occupation if he is not qualified.

        Jews could as well be low skilled workers if farming was deliberately forbidden to them. But somehow ashkenazim got all these white collar jobs. There is something else going on here.

        The Amish “only” farm, and it does not seem to effect their intelligence.

        So I think, this high biological intelligence resulted in those lifestyles. Ashkenazim was just a smarter fraction of jews coming from Middle East. Jews were smarter from the beginning. They created a religion that still effects whole world (including christianity and islam having judaic roots).

    • DataExplorer says:

      I read that the Sephardic Jewish population of Italy before WW2 was under 50,000, from that population they produced 4 Nobel Prize winners (3 in sciences and 1 in economics):
      Salvador Luria, Rita Levi-Montalcini, Emilio Segrè, and Franco Modigliani. Venezuela’s only winner was also Sephardic: Baruj Benacerraf, in medicine.

      • Larry, San Francisco says:

        And Modigliani’s uncle was one of the great painters of the 20th century. Many economic departments have copies of his prints in their office

  9. epoch2013 says:

    “It’s not impossible that the admixture happened at the same time as the founding. This I didn’t expect.”

    Could it be due to some persecution event? Expulsion from south after pogroms leading to the need for more… women? Fresh blood? Perhaps numbers fell dangerously and the strict Jewish rules for converts became more lax? More or less like current-day Samaritans nowadays allow marriage to non-Samaritan women in order not to go extinct.

    • epoch2013 says:

      I see similar ideas were entertained in the previous thread. Biggest issue with it is that Italy as a whole seemed to be rather peaceful for Jews during the early Middle Ages, unlike Spain. Apart from the southern, Byzantine part where conversions were forced.

    • epoch2013 says:

      Italy being one of Europe’s most genetic divers countries one would think the Italian admixture could be traced more specifically.

  10. dearieme says:

    Rome’s population: any relevance?

    Population peaked at the height of imperial power in the early 2nd century. Then, with the Antonine Plague and the Crisis of the Third Century it declined, at first gradually, then, with the collapse of the Western Roman Empire, catastrophically.

    year (AD) 100 300 400 450 500 550 600 752
    pop. 1,650,000 1,200,000 1,100,000 500,000 100,000 50,000 90,000 40,000

    Middle Ages and Renaissance
    Rome reached its nadir during the Avignon Papacy. It gradually recovered during the Roman Renaissance, but was again devastated in 1527.

    year 800 1000 1347 1519 1527 1590 1660
    pop 50,000 30,000 17,000 50,000 32,000 90,000 120,000

  11. dearieme says:

    Wot, like this?

    ^ mary had a little lamb
    she also had a bear^

  12. dearieme says:

    ^mary^ ^had a little lamb^
    ^she also had^ ^a ^ ^bear^

    • dearieme says:


    • MawBTS says:

      Sorry senor/senora, the ^ wasn’t code, it was just a directional arrow to the above post. Here’s the HTML tags WordPress supports, you want pre.

      If you want to test something, just post a comment on one of the millions of abandoned WordPress blogs lying around the internet.

  13. Unladen Swallow says:

    Greg, regarding the breakdown of the European component, how much would be Italian-Southern French, and how much would be German and/or Slavic/Baltic? Is 30 years the length of a generation?

  14. Jacob Weisser says:

    How can you account for the supposed large Italian maternal ancestry of Ashkenazim considering the lack of IBD sharing? According to the most current hypothesis the admixture wasn’t that long ago, and unless Ashkenazim had abnormally high mutation rates (unlikely, not even sure how that would work) I can’t think of how IBD shared segments could decrease that rapidly (I don’t think genetic drift applies here, as if shared segments with Italians were randomly selected out, then why would we come to the conclusion that Ashkenazim were admixed at all? (in this Hebrew + Italian hypothesis)).

    As I’m sure you accept, many regions in Europe and the Middle East aren’t what they used to be, phenotypically (and thus also genetically, to whatever extent). Tacitus described the Germanic tribes (wherever they were – from the Lower Rhine to the Upper Danube) as appearing more or less like modern Northern Dutchmen, yet go to Bavaria and you’ll see nothing of the sort. Ancient Greek authors described both the Thracians and Spartans as being red-headed, and the same with many Trojan figures too. Rameses II was a redhead, as was (despite being fictional) King David. A handful of Egyptian mummies are even blonde, dating well before the Ptolemaic dynasty. It isn’t very useful to envision mixing scenarios to modern populations when many of these modern populations have gone through massive genetic change, though populations like the Samaritans and the Yazidis retain some of these features to some extent.

    Red-headedness can clearly be seen by peoples carrying R1b-like admixture (yes, I know the Y DNA won’t encode for the red-headedness itself). Because these R1b tribes were so alpha (which has basically continued even today if you look at world history, but anyway), the men were rarely beaten and would instead take women for themselves, so we generally see an association between Y DNA R1b and red-headedness (with the association stronger in Northern Europe, as in for example Southern Europe there were many Mediterranean women for pickings, which diluted the R1b-like red-headed admixture). Well, most early branches of R1b developed in the Middle East (pre-Indo-European – these Middle Eastern R1b tribes moving up to the Pontic-Caspian Steppe is the origin of R1b and the CHG component in Yamnaya, and really the formative event in the creation of the Indo-Europeans (it also explains why the Anatolian branch is more archaic)), more specifically in the Anatolia-Armenia region. Even before that, European hunter-gatherers operated well into that region, as evidenced by the distribution of Y DNA I extending well into the Northern Fertile Crescent, but also potentially by things like blue eyes on many Sumerian sculptures. (Relatively) more recently, the Iranian branch of Indo-Europeans invaded parts of the Middle East through Persia too, which would have brought some element of blondism (though to expect these invaders to have been majority blonde hair and blue eyed is ridiculous – this element would naturally be diluted from the original proto-Indo-Iranians).

    So, I’ve basically rambled at how the Middle East, but more specifically Western Asia in general (not really Arabia), would have had a lot more European-like admixture then as compared to now, at least based from phenotypes. I won’t even think about jumping to the conclusion that Ashkenazim are somehow mostly pure since that period, and that the Middle East has just been genetically transformed by Arabs (and to some extent SSA) leaving no survivors, as that is an insane (and almost Judeo-supremacist in the case of this argument) hypothesis, but things like the disappearance of red-headedness in the region (yet continuation in Ashkenazim – Ashkenazim have roughly the same amount of red-headedness as Belgians, which is pretty unexpected and “impressive”), as well as the complete lack of IBD sharing with Italians, have to be accounted for when considering Ashkenazic origins. The Italian hypothesis cannot account for this, at all, as it is a pretty poor argument to claim Ashkenazi pigmentation was selected for to such an extent in the bottleneck as to turn a light olive population in many cases (certainly in mine) ghostly pale (and the same for red hair etc.).

    To my mind, if we take Cypriots as a proxy for ancient Levantine peoples, which I think is entirely fair (but even if you use Christian Lebanese you see similar results), we do see Ashkenazim as a roughly 50/50 split between Tuscan and Cypriot populations, at least on PCA plots, which matches roughly the current model. However, like many on the forums have speculated, I think this admixture pulling Ashkenazim generally in the direction of Europe is mainly Balkano-Anatolian – not with a modern Balkano-Anatolian population, but rather one with more R1b-like admixture (so with an EEF-NW Euro population on a similar axis as the line from the PCA plots of Tuscan/Greek populations to modern Ashkenazim) that increased the NW Euro component among Ashkenazim (and the WHG component somewhat too, as among Cypriots it’s actually negative)). This explains a number of things. Firstly, it explains Ashkenazic pigmentation being as light and red-headed as it is (as an example, Antinous was naturally blonde and from Anatolia – it is with Antinous-like women that I believe the Italian-esque mtDNA is originally from, especially given a lot of Italian mtDNA can be traced back to Anatolia).

    In support of this idea is firstly historical – the most widespread period of proselytising among Jews is during the Hellenistic period (see Philo of Alexandria). Also, in medieval Spain and Italy (yes, I know this applies to Sephardim, although you have to ask why Sephardim are noticeably darker than Ashkenazim – perhaps they mixed more (in their ethnogenesis) with darker populations than Ashkenazim), red-headedness was supposed to be a sign of Jewish ancestry – this clearly points to an admixture event before Jews entered Western Europe from the Mediterranean, unless Jews were originally extremely red-headed and merely became less so by mixing with swarthier Southern Europeans (which is unlikely, as you would have thought the Romans would have mentioned if Jews were so incredibly red-headed – though I do believe Jews would have been more red-headed than basically everybody in the Middle East currently is from the get go).

    So, for a tl;dr, we can presume, from Ashkenazi red-headedness (assuming Ashkenazim weren’t originally even more red-headed), the lack of IBD sharing with Italians, and various historical facts mentioned so far, that: the admixture event occurred before Jews entered Western Europe from the Mediterranean, as they must have mixed with a very red-headed population (which definitely is not from Italy, unless the Roman aristocracy was very red-headed), and that this mixing with a bunch of red-heads probably happened during the Hellenistic period, and that it did not occur with a population heavy in WHG ancestry. From these criteria, the only population that could possibly satisfy this is a now mixed Balkano-Anatolian population, plotting roughly on the Tuscan/Greek to Ashkenazic axis on PCA plots. We know that such a population existed, as mentioned earlier on in this mini-essay. Also, such a population would have been widespread in the Hellenistic period in particular. Furthermore, it may have only been the upper echelons of that population that had these rufous features, as you have to ask why (for example) modern day Greeks and Anatolians are so dark today.

    An alternative to this hypothesis that rectifies the issue of red-headedness is that populations from the Northern Fertile crescent were always extremely red-haired (I believe they definitely used to be a lot more than at the moment at least), and that either the Mesopotamian hypothesis of Hebrew origins is correct, or that Ashkenazic red hair comes from mixing with these Mesopotamian populations while in captivity. Not only is this unlikely to me, but it also doesn’t explain the lack of IBD sharing with Italians.

    If you disagree with this, that’s fine, but instead of pointing to the Costa et. al paper that shows Italian mtDNA is more similar to Ashkenazic mtDNA than modern Middle Eastern populations, I’d like an alternate hypothesis that actually explains Ashkenazic pigmentation.

    And if you’ve read this far through my presumable bad grammar (unchecked), congrats!

    • Jacob Weisser says:

      Here’s the PCA plot in question:

      And here’s a map of Ashkenazic IBD sharing (supposedly – though I know for sure there’s a lack of IBD sharing with Italians (and curiously a decent amount of IBD sharing with East Europeans, though I suspect this is either from outward flow (Jewish to Slav) or because this supposed Balkano-Anatolian population originally had similarities with Eastern Europeans (which I suppose makes sense if you consider that this population would have been more Northern-shifted than the Balkans currently is, yet at the same time it’s NW Euro component would undoubtably be stronger than its Eastern European component – this is actually a similar pseudo-paradox to the Corded Ware population, which has its roots in Eastern Europe and is mostly (to a very clear degree) Y DNA R1a, yet has a much higher NW Euro component than East Euro):

    • gcochran9 says:

      IBD segments get shorter with time: recombination.

      As for the rest, you’re just utterly wrong.

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